Abstract: ObjectiveTo investigate the influence of nalmefene hydrochloride on the analgesic effects, respiratory depression and adverse reaction of sufentanil during laparoscopic hysterectomy under intravenous anesthesia. MethodsSixty ASA I-II patients who were scheduled to undergo laparoscopic hysterectomy under intravenous anesthesia were enrolled. They were randomly divided into three groups (n=20): a nalmefene postoperative injection group giving nalmefene 5 min after the end of surgery, a nalmefene preoperative injection group injected with nalmefene 5 min before anesthesia induction and a blank control group without nalmefene injection. The recovery time of spontaneous breathing, time to open eyes, extubation time, visual analogue analgesia score (VAS) at 1, 8 and 24 h after surgery, Ramsay scores 5, 30 and 60 min after extubation and adverse reactions such as restlessness, nausea and vomiting, and respiratory depression were recorded. ResultsCompared with the black control group, the nalmefene postoperative and preoperative injection groups showed remarkable decreases in postoperative spontaneous breathing recovery time, time to open eyes, extubation time, Ramsay scores at difference time points and adverse reactions (P<0.05). There was no significant difference as to the above indexes between the nalmefene postoperative and preoperative injection groups (P>0.05). No significant difference in VAS among the three groups at all time points (P>0.05). ConclusionsNalmefene hydrochloride can antagonize the respiratory depression and reduce the incidence of adverse reactions after sufentanil administration, without significant effects on postoperative analgesic effects.